Communication system having railway vehicle-side and trackside communication devices and method for the operation thereof

ABSTRACT

A railway vehicle-side communication device for a railway vehicle for communicating with a trackside communication device. The trackside communication device has at least two communication modes, namely, a first communication mode having a first data transfer rate and a second communication mode having a second data transfer rate that is higher than the first data transfer rate. The railway vehicle-side communication device has a switch-over element setting the second communication mode in or in the vicinity of a station for communicating with a station-side communication device and setting the first communication mode outside of a station for communicating with a track-side communication device.

The invention relates to a communication device on the rail vehicle side for a rail vehicle for communication with a trackside communication device.

By way of example, communication devices such as these are known in conjunction with automatic train control systems which allow the train to be controlled by trackside control or monitoring centers.

Against the background of a communication device such as this, the invention is based on the object of developing this device further such that more data than in the past can be transmitted in total during operation of the rail vehicle.

According to the invention, this object is achieved by a communication device on the rail vehicle side as claimed in patent claim 1. Advantageous refinements of the communication device according to the invention are specified in dependent claims.

The invention accordingly provides that the communication device on the rail vehicle side has at least two communication modes, specifically a first communication mode at a first data transmission rate and a second communication mode at a second data transmission rate, which is higher than the first data transmission rate, and in that the communication device on the rail vehicle side has a switching device which selects the second communication mode in the station or in the vicinity of a station for communication with a communication device on the station side, and selects the first communication mode outside a station, for communication with a trackside communication device.

One major advantage of the communication device according to the invention is that this device allows larger amounts of data to be transmitted than previous communication devices. Specifically, this is because the communication device according to the invention provides two communication modes which are each matched to the respective location of the rail vehicle. Specifically, when a train is on a track between two stations, the maximum data transmission rate when the rail vehicle is travelling at high speed is generally limited for technical reasons, which means that only a relatively low data rate can be transmitted while operating between the stations. In contrast, when the rail vehicle is moving only slowly or is stationary, as is the case in the station area for example, then higher data rates can be achieved, which means that relatively large amounts of data can be transmitted overall as well, in a relatively short time. This is the purpose of the invention, which provides for the communication device on the rail vehicle side to have a switching device which selects a location-specific communication mode depending on the location of the rail vehicle. In this case, in the station area, while the rail vehicle is quite slow or is stationary, a high data transmission rate is selected and, in the area outside a station, a lower data rate than this is selected, in order to allow error-free or low-error data transmission at relatively high speeds.

A further major advantage of the communication device according to the invention is that it can be used even when the operator wishes to use high bit-rate data transmission, as is required for example with driverless rail vehicles and/or in the case of video monitoring of the rail vehicle interior from the track.

The operating mode switching can be carried out particularly easily and therefore advantageously by the switching device being connected to a motion or speed sensor and being designed such that it switches from the first to the second communication mode when the rail vehicle is travelling at less than a predetermined speed, and switches from the second to the first communication mode when the rail vehicle is travelling above the predetermined speed. In this advantageous refinement of the communication device, the communication modes are therefore switched as a function of the speed, with the speed being used to decide whether the rail vehicle is or is not in a station area.

Alternatively or additionally, the switching device can also be connected to a position determining device and can be designed such that it switches from the first to the second communication mode when the position determining device signals proximity to a station, and switches from the second to the first communication mode when the position determining device signals a track outside a station. By way of example, a position determining device such as this may be formed by an automatic train monitoring system or may comprise such a system; specifically, for the purposes of automatic train monitoring, a continuous determination is made as to where a rail vehicle is located, thus resulting in a position definition signal by evaluation of the corresponding measurement signals, which position definition signal can be used to select the correct communication mode.

In addition, the switching device may also itself be suitable to use received signals which are received from trackside communication devices to determine whether these devices form a communication device on the station side or a trackside communication device. The switching device can make such a decision on the basis of the received signals for example by evaluating the Standard used as the basis for production of the received signals, and/or the transmitted powers of these signals and/or what specific reception characteristics can be identified.

The communication device preferably has at least two transmitting and receiving devices, which are arranged at a distance from one another in the rail vehicle, in the vehicle longitudinal direction, in the vehicle lateral direction or one above the other, or one below the other. This is because the fitting of two or more transmitting and receiving devices at a distance from one another in this way allows these devices to be operated with different data, thus allowing parallel data transmission. In this case, the maximum achievable data rate is governed by the number of transmitting and receiving devices multiplied by the data rate of a single transmitting and receiving device.

If the rail vehicle is a train, then it is considered advantageous for at least one transmitting and receiving device to be arranged in or on the front vehicle of the train and/or at least one transmitting and receiving device to be arranged in or on the rearmost vehicle in the train.

Irrespective of how many transmitting and receiving devices are provided on the rail vehicle side, it is considered to be advantageous for them to be arranged offset, in particular in the vehicle longitudinal direction, such that the distance between the transmitting and receiving devices is greater than the interference range, which can be determined for example by the transmitted power, in the vehicle longitudinal direction.

Because the aim is to transmit as large an amount of data as possible, it is considered to be advantageous for data which is as different as possible, even if these are not data items which are necessarily independent of one another, to be transmitted via a plurality of transmitting and receiving devices, and as far as possible to avoid redundancy.

In order to allow parallel transmission of data for station operation, it is considered to be advantageous for the transmitted power of the communication device on the rail vehicle side to be lower in the second communication mode than in the first communication mode; this is because a refinement such as this ensures that the individual transmitting and receiving devices in the communication device on the rail vehicle side cannot interfere with one another when they communicate with the communication device on the station side by being operated in parallel.

The communication device on the rail vehicle side preferably has one or more reception filters whose reception sensitivity is variable, in order to allow an optimum reception quality to be selected; in this case, the communication device is preferably also designed such that it selects the reception sensitivity as a function of the respective communication mode, to be precise such that the reception sensitivity in the first communication mode is higher than in the second communication mode. Sensitivity control such as this is particularly advantageous when the aim is to carry out parallel data transmission using a plurality of transmitting and receiving devices at the same time in the second communication mode, that is to say in the station area, with the aim of avoiding mutual inference or disturbances.

The communication device on the rail vehicle side particularly preferably also has at least one infrared transmission device which can communicate in the second communication mode with a corresponding infrared transmission device on the station side.

The communication device is preferably equipped with at least two infrared transmitting and infrared receiving devices which are arranged at a distance from one another in the rail vehicle, in particular in the vehicle longitudinal direction. A refinement or arrangement of the infrared transmitting and infrared receiving devices such as this allows data to be transmitted in parallel by optical means, thus allowing very large amounts of data to be transmitted overall.

It is also considered to be advantageous for the communication device on the rail vehicle side to be equipped with a radio transmission device which—for example for the first communication mode—can communicate with a trackside communication device by radio. By way of example, a refinement such as this makes it possible to transmit data in the station area by infrared light, and on the track by radio.

Furthermore, it is possible to design the radio transmission device on the rail vehicle side to be switchable in such a way that it is also possible to communicate by radio with a communication device on the station side, to be precise in the second communication mode.

The radio communication using the second communication mode preferably takes place using a different radio standard than radio communication in the first communication mode. For example, it is possible to transmit data using the WLAN-B Standard with a data rate of between 5 and 10 Megabits per second on the track and to select the WLAN-G Standard, with a data rate of 50 Megabits per second, in the station area.

Furthermore, the invention relates to a rail vehicle which is equipped with a communication device on the rail vehicle side as described above.

Furthermore, the invention relates to a communication system having a communication device on the rail vehicle side, as has been described above, having at least one communication device on the station side, and at least one trackside communication device, wherein the trackside communication device has a first communication mode at a first data transmission rate, and the communication device on the station side has a second communication mode at a second data transmission rate, which is higher than the first data transmission rate.

With regard to the advantages of the communication system according to the invention, reference should be made to the above statements in conjunction with the communication device according to the invention, since the advantages essentially correspond to one another.

With regard to the communication system, it is considered to be advantageous for the communication device on the rail vehicle side to have at least two transmitting and receiving devices which are arranged at a distance from one another in the rail vehicle, in particular in the vehicle longitudinal direction and, when there are at least two transmitting and receiving devices on the station side, for them to be arranged offset, in particular in the station longitudinal direction. The distance between the transmitting and receiving devices on the rail vehicle side and the transmitting and receiving devices on the station side is preferably the same, or preferably at least approximately the same, in order that they can form transmitting/receiving pairs with one another.

In a corresponding manner, it is considered to be advantageous for the transmitting and receiving devices on the station side to be arranged such that the transmitting and receiving devices on the rail vehicle side and the transmitting and receiving devices on the station side are opposite in pairs when the rail vehicle has reached its stopping position in the station. The corresponding transmitting and receiving devices on the station side may, for example, be arranged in the track bed or in the platform area.

The transmitting and receiving devices on the station side are particularly preferably infrared transmitting and infrared receiving devices, since these can transmit relatively high data rates over short distances and are relatively insensitive to interference in the process.

Furthermore, the invention relates to a communication device on the station side as can be used, for example, for the described communication system, wherein the communication device has at least two transmitting and receiving devices which are arranged at a distance from one another in the station longitudinal direction.

With regard to the advantages of the communication device on the station side, reference should be made to the above statements in conjunction with the communication device according to the invention on the rail vehicle side, and the described communication system according to the invention.

The communication device on the station side preferably has a plurality of transmitting and receiving devices which are arranged offset in the station longitudinal direction, with the distance between the transmitting and receiving devices being greater than the interference range in the station longitudinal direction which is governed, for example, by their transmitted power, orientation or type.

Furthermore, the invention relates to a method for operating a communication device on the rail vehicle side. For a method such as this, the invention provides that switching takes place from a first communication mode at a first data transmission rate to a second communication mode at a second data transmission rate, which is higher than the first data transmission rate, when the rail vehicle stops in or in the vicinity of a station, and switching takes place from the second communication mode to the first communication mode when the rail vehicle is located outside a station.

The invention will be explained in more detail in the following text with reference to one exemplary embodiment, which is illustrated in more detail in FIG. 1.

FIG. 1 shows a communication system 10, of which FIG. 1 illustrates a communication device 20 on the rail vehicle side, which is fitted in or to a rail vehicle 15, a communication device 30 on the station side and three trackside communication devices 40, 50 and 60.

The communication device 20 on the rail vehicle side has two transmitting and receiving devices 70 and 80, which are connected to a switching device 90 for switching the communication mode of the two transmitting and receiving devices 70 and 80. The two transmitting and receiving devices 70 and 80 are at a distance A from one another. One of the two transmitting and receiving devices 70 and 80 is preferably located—seen in the direction of travel—as far forward as possible, and the other is located as far to the rear as possible, in the rail vehicle 15.

The three trackside communication devices 40, 50 and 60 and the communication device 30 on the station side are connected to a trackside central control unit 100, which operates the trackside communication devices and the communication devices on the station side and is used for transferring, that is to say transmitting and receiving, data.

In the exemplary embodiment shown in FIG. 1, the rail vehicle 15 is located in a station, as a result of which the two transmitting and receiving devices 70 and 80 can communicate with corresponding transmitting and receiving devices 170 and 180 on the station side, of the communication device 30 on the station side.

The distance between the transmitting and receiving devices 170 and 180 on the station side is annotated with the reference symbol B in FIG. 1. The two distances A and B are preferably the same, or at least approximately the same, as a result of which pairs of transmitting and receiving devices are formed, which are opposite one another. In the exemplary embodiment shown in FIG. 1, the transmitting and receiving device 70 is opposite the transmitting and receiving device 170 on the station side. A corresponding situation applies to the transmitting and receiving devices 80 and 180, which likewise form a pair.

The two transmitting and receiving devices 170 and 180 on the station side are preferably infrared devices, which communicate with the associated transmitting and receiving devices 70 and 80, respectively, on the rail vehicle side via an infrared link.

Alternatively, it is also possible for the transmitting and receiving devices 170 and 180 on the station side to be radio devices, as a result of which the corresponding links between the transmitting and receiving devices 70 and 80 on the rail vehicle side and the transmitting and receiving devices 170 and 180 on the station side are provided by radio path.

When the rail vehicle 15 leaves the station, then the communication between the communication device 20 on the rail vehicle side and the communication device 30 on the station side is terminated and is replaced by communication with the trackside communication devices 40, 50 or 60. Since low-error data transmission is difficult for technical reasons at high rail vehicle speeds, the communication device 20 on the rail vehicle side will switch the communication mode when outside the station, and will switch it to a different communication mode, in which a lower data transmission rate is selected. The communication link to the trackside communication devices 40, 50 and 60 is in this case preferably provided on the radio path.

The communication device 20 on the rail vehicle side can decide in various ways whether it is in a station area or on a track between stations. The communication device 20 on the rail vehicle side preferably assesses a motion or speed measured value from a motion or speed sensor, and/or a signal from a position determining device. Alternatively or additionally, the communication device 20 in the rail vehicle or on the rail vehicle side can also evaluate signals received from the trackside communication devices 40, 50 or 60 or from the communication devices 30 on the station side, and can use the received signals to decide whether the rail vehicle 15 is or is not in a station area. Such determination of the location on the basis of the received signals is possible, for example, when the trackside communication devices 40, 50 and 60 use a different data rate and/or a different radio standard than the corresponding communication devices 30 on the station side. 

1-24. (canceled)
 25. A communication device on a rail vehicle for communication with a trackside communication device, comprising: the communication device on the rail vehicle side having at least two communication modes including a first communication mode at a first data transmission rate and a second communication mode at a second data transmission rate, the second data transmission rate being higher than the first data transmission rate; and a switching device of the communication device on the rail vehicle side, said switching device being configured to select the second communication mode in a station or in a vicinity of a station for communication with a communication device at a station, and to select the first communication mode outside a station, for communication with the trackside communication device.
 26. The communication device on the rail vehicle side according to claim 25, wherein said switching device is connected to a motion or a speed sensor and configured to switch from the first communication mode to the second communication mode when the rail vehicle is travelling at less than a predetermined speed, and to switch from the second to the first communication mode when the rail vehicle is traveling above the predetermined speed.
 27. The communication device on the rail vehicle side according to claim 25, wherein said switching device is connected to a position-determining device and is configured to switch from the first communication mode to the second communication mode when the position determining device signals proximity to a station, and to switch from the second communication mode to the first communication mode when the position determining device signals a track outside a station.
 28. The communication device on the rail vehicle side according to claim 27, wherein the position determining device is formed by or comprises an automatic train monitoring system.
 29. The communication device on the rail vehicle side according to claim 25, wherein said switching device is configured to determine, from the signals received whether the signals are received from a communication device at the station or a trackside communication device.
 30. The communication device on the rail vehicle side according to claim 25, which comprises at least two transmitting and receiving devices disposed at a spacing distance from one another in the rail vehicle.
 31. The communication device on the rail vehicle side according to claim 25, wherein said at least two transmitting and receiving devices are disposed at a spacing distance along a vehicle longitudinal direction.
 32. The communication device on the rail vehicle side according to claim 30, wherein the rail vehicle is a train, at least one transmitting and receiving device is disposed in or on a first vehicle of the train, and at least one transmitting and receiving device is disposed in or on a rearmost vehicle of the train.
 33. The communication device on the rail vehicle side according to claim 25, which comprises a plurality of transmitting and receiving devices disposed with an offset in the vehicle longitudinal direction, wherein a distance between said transmitting and receiving devices is greater than an interference range in a vehicle longitudinal direction, predetermined by a transmitted power thereof.
 34. The communication device on the rail vehicle side according to claim 30, wherein said transmitting and receiving devices are configured to simultaneously transmit and/or receive mutually different data.
 35. The communication device on the rail vehicle side according to claim 25, wherein a transmitted power of the communication device on the rail vehicle side is lower in the second communication mode than in the first communication mode.
 36. The communication device on the rail vehicle side according to claim 25, wherein the communication device on the rail vehicle side is configured such that, when the communication device on the rail vehicle side has a reception filter, the device selects a higher reception sensitivity in the first communication mode than in the second communication mode.
 37. The communication device on the rail vehicle side according to claim 25, which comprises at least one infrared transmission device configured to communicate in the second communication mode with an infrared transmission device on the station side.
 38. The communication device on the rail vehicle side according to claim 25, which comprises at least two infrared transmitting and infrared receiving devices disposed at a distance from one another in the rail vehicle.
 39. The communication device on the rail vehicle side according to claim 38, wherein said at least two infrared transmitting and infrared receiving devices are disposed at a distance from one another in a vehicle longitudinal direction.
 40. The communication device on the rail vehicle side according to claim 25, which comprises a radio transmission device configured to communicate in the first communication mode with a trackside communication device by radio.
 41. The communication device on the rail vehicle side according to claim 40, wherein said radio transmission device on the rail vehicle side can be switched between different radio standards and, in the second communication mode, can communicate with a communication device on the station side by radio, to be precise based on a different radio standard than that for communication in the first communication mode.
 42. A rail vehicle, comprising a communication device according to claim
 25. 43. A communication system, comprising: a communication device on the rail vehicle side according to claim 25; at least one communication device on a station side and having at least one trackside communication device; said trackside communication device having a first communication mode at a first data transmission rate and said at least one communication device on the station side having a second communication mode at a second data transmission rate, which is greater than the first data transmission rate.
 44. The communication system according to claim 43, wherein said communication device on the rail vehicle side has at least two transmitting and receiving devices which are arranged at a distance from one another in the vehicle longitudinal direction in the rail vehicle, and wherein at least two transmitting and receiving devices are disposed on the station side and are arranged offset in the station longitudinal direction, wherein a distance between the transmitting and receiving devices on the rail vehicle side and the transmitting and receiving devices on the station side is at least substantially equal.
 45. The communication system according to claim 44, wherein said transmitting and receiving devices on the station side are arranged such that the transmitting and receiving devices on the rail vehicle side and the transmitting and receiving devices on the station side are opposite in pairs when the rail vehicle reaches its stopping position in the station.
 46. The communication system according to claim 43, wherein said transmitting and receiving devices on the station side are infrared transmitting and infrared receiving devices.
 47. A communication device on a station side of a railway system, comprising at least two transmitting and receiving devices, disposed at a mutual spacing distance in a longitudinal direction of a railway station of the railway system.
 48. The communication device according to claim 47 configured for the communication system according to claim
 43. 49. The communication device on the station side according to claim 48, which comprises a plurality of transmitting and receiving devices arranged offset in the station longitudinal direction, wherein a distance between said transmitting and receiving devices is greater than an interference range in their station longitudinal direction, which is predetermined by a transmitted power thereof.
 50. The communication device on the station side according to claim 49, wherein said transmitting and receiving devices on the station side are infrared transmitting and infrared receiving devices.
 51. A method of operating a communication device on a rail vehicle, which comprises: providing a communication device configured to be switched between a first communication mode, having a first data transmission rate, and a second communication mode, having a second data transmission rate greater than the first data transmission rate; switching from the first communication mode at the first data transmission rate to a second communication mode at the second data transmission rate, when the rail vehicle stops at or in a vicinity of a railway station; and switching from the second communication mode to the first communication mode when the rail vehicle is located outside a station.
 52. The method according to claim 51, wherein the providing step comprises providing a communication device according to claim
 25. 